As the conventional false-twisted filament yarn suitable for the production of a fabric having a combination of a soft touch and an appropriate resilience, a mixed false-twisted filament yarn having entangled portions and open portions thereof appearing intermittently in the longitudinal direction, which is prepared by blending and entangling at least two types of filaments having different denier by a pneumatic blending apparatus such as a Taslan nozzle or an interlacing nozzle, is known from, for example, Japanese Examined Patent Publication No. 47-18060.
The entangled portions of this type of false-twisted filament yarn are formed intermittently along the longitudinal direction, and larger denier filaments form cores and smaller denier filaments form coverings (sheaths) in these portions.
In this type of mixed false-twisted filament yarn, a bundling property is given by the entangled portions thereof and a bulkiness is imparted by opened portions formed between the entangled portions. The touch of a fabric obtained from this false-twisted filament yarn is soft, but the resilience is relatively low.
In a mixed false-twisted filament yarn obtained by blending a plurality of crimped multifilaments having a different denier by a pneumatic blending apparatus, the larger denier filaments and the smaller denier filaments in the interior of the yarn are easily separated from each other, and in the opened portions of this yarn, the opened smaller denier filaments cover a core composed mainly of the larger-denier filaments in a state wherein the smaller-denier filaments extend substantially in parallel to the longitudinal axis of the yarn. Accordingly, it is difficult to uniformly cover the core composed of the larger-denier filaments with the smaller-denier filaments, and therefore, if a fabric formed from the false-twisted filament yarn is dyed, an uneven dyeing occurs because of the uneven distribution of the larger-denier filaments and smaller-denier filaments, especially smaller denier filaments, and an uneven coloration of the dyed fabric is obtained.
To eliminate the above defect of the conventional mixed false-twisted filament yarn, the present inventors changed the denier in the larger-denier filaments and/or smaller-denier filaments constituting the false-twisted yarn, but found it was difficult to obtain a mixed false-twisted filament yarn which can be converted to a fabric having a very soft touch, a good bulkiness, a sufficient resilience, a good crease recovery, and a uniform appearance, even after dyeing.